package com.xucan.catchx;

import java.util.Map;

public class NullpOint {
    private Map map;

    public NullpOint(Map map) {
        this.map = map;
    }

    public void test(Map map) {
        NullpOint nullpOint = new NullpOint(map);
    }
    public static void main(String[] args) {
        int index = "Hellox, Worldx".lastIndexOf("d"); // 返回0
        System.out.println(index);

//        Integer a=1;
//        String s = "1";
//        System.out.println(a.equals(s));
//        System.out.println();
    }
}
